Beshears et al., U.S. Pat. Pub. No. US2006/0111868, assigned to the party of interest herein, discloses a system that automatically obtains the following data from a vehicle that is driven slowly (≦5 MPH) over multiple weigh-pads on smooth asphalt or concrete surfaces: weight on each tire; single-axle weights; total vehicle weight; axle spacings; longitudinal and transverse centers of balance; and wheel spacing on each axle.
Abercrombie et al., U.S. patent application Ser. No. 11/583,473, also assigned to the party of interest herein, describes the operation of the system to determine vehicle length, width, and height, and an estimate of the vehicle volume from two-dimensional digital images.
Walker et al., U.S. patent application Ser. No. 11/703,992, also assigned to the party of interest herein, describes use of the system for vehicle identification via radio-frequency ID tag or barcode and for vehicle inspection and cargo characterization.
Alternative methods use static measurement of vehicle weight, a tape measure for determining axle distances, manual recording of individual axle weights and distances, manual calculation of total vehicle weight and center of balance, and manual entry of the results into a computer system.
U.S. Federal and State agencies need certifiable vehicle weights for various applications, such as highway inspections, border security, check points, and port entries.
Before implementing the present invention, the error in total weight for a vehicle was greater than the error in weighing on in-ground scales (IGS) and greater than 0.1%. The weigh-in-motion system of the prior art was not capable of providing certifiable weights, due to natural oscillations, such as vehicle bouncing and rocking and other vehicle dynamics during weighing activities.